This invention is in the field of microstructures, i.e., structures which have one or more dimensions measured in microns. Nowadays it is not uncommon for electronic integrated circuits to have elements with such measures. These circuits, unless they are multiple-layered, are essentially planer and thin layered, with the elements partially or wholely infused into a substrate, or tightly bound to the substrate, with no space between elements and substrate. For multiple-layered circuits, successive layers are tightly bound to previous layers, with no space therebetween. Various techniques are used to produce such circuits, such as masking, etching, ion implanting in various ways, laser, ion, electron beam, and plasma milling, etc. Wet chemical etching and milling with charged particles or plasmas are highly satisfactory techniques when one is working with such tightly bound layers. If, however, one is fabricating a microstructure with spaces between thin layers or between thin layers and a substrate, surface tension from wet etching and charge buildup from plasma or charged particles can destroy such layers. Examples of microstructures is which such spaces may be desirable are: multiple-layer integrated circuits in which gas or vacuum dielectric is needed between portions of layers (obviously, something much be left to physically support successive layers), arrays of thermal detectors, integrated optical circuits, acoustic transducer arrays, and flat panel displays.
The present invention can produce microstructures will space between closely-spaced layers or between such layers and a substrate.